Android开发之底部导航栏标准

以下是封装的库源码：

 package com.example.oldtab;

 import java.util.ArrayList;

 import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.support.v4.app.FragmentTabHost;
 import android.support.v7.app.ActionBarActivity;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.widget.TabHost;
 import android.widget.TextView;

 public class NsFragmentTabHost implements TabHost.OnTabChangeListener {
     private FragmentTabHost fragmentTabHost;
     private LayoutInflater layoutInflater;
     private Resources resources;
     private ArrayList<NsFragmentItem> tabs;
     private NsFragmentItem preItem;

     NsFragmentTabHost(FragmentTabHost tabhost, ActionBarActivity activity) {
         this(tabhost, activity, android.R.id.tabcontent);
     }

     NsFragmentTabHost(FragmentTabHost tabhost, ActionBarActivity activity,
             int realContentid) {
         fragmentTabHost = tabhost;
         tabs = new ArrayList<NsFragmentItem>();
         layoutInflater = activity.getLayoutInflater();
         resources = activity.getResources();
         tabhost.setup(activity.getBaseContext(),
                 activity.getSupportFragmentManager(), realContentid);
         tabhost.setOnTabChangedListener(this);
     }

     public View newTabView(int layoutid, int backgroung, String title) {
         TextView tv = (TextView) layoutInflater.inflate(layoutid, null);
         tv.setText(title);
         Drawable draw = resources.getDrawable(backgroung);
         tv.setCompoundDrawablesWithIntrinsicBounds(null, draw, null, null);
         return tv;
     }

     public void AddTab(NsFragmentItem item) {
         tabs.add(item);
         fragmentTabHost.addTab(fragmentTabHost.newTabSpec(item.tag)
                 .setIndicator(item.view), item.fragment, null);
     }

     public NsFragmentItem getTabByTag(String tag) {
         for (NsFragmentItem item : tabs) {
             if (item.tag == tag) {
                 return item;
             }
         }
         return null;
     }

     @Override
     public void onTabChanged(String tabId) {
         NsFragmentItem item = getTabByTag(tabId);
         if (item != null) {
             if (preItem != null) {
                 preItem.view.setBackgroundResource(preItem.upStyle);
             }
             preItem = item;
             item.view.setBackgroundResource(item.downStyle);
         }
     }

     public static class NsFragmentItem {
         public View view;
         public String tag;
         public Class<?> fragment;
         public int downStyle;
         public int upStyle;
     }
 }

下面就是示例，如何使用上面的库

 package com.example.oldtab;

 import android.os.Bundle;
 import android.support.v4.app.FragmentTabHost;
 import android.support.v7.app.ActionBarActivity;
 import android.view.View;

 import com.example.oldtab.NsFragmentTabHost.NsFragmentItem;

 public class Main extends ActionBarActivity {

     private static final String TAG_PERSON = "person";
     private static final String TAG_GROUP = "group";
     private static final String TAG_SETTING = "setting";

     private NsFragmentTabHost nsTabHost;
     private FragmentTabHost tabHost;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         tabHost = (FragmentTabHost) findViewById(android.R.id.tabhost);
         nsTabHost = new NsFragmentTabHost(tabHost, this, R.id.realtabcontent);
         View i1 = nsTabHost.newTabView(R.layout.tabitem,
                 R.drawable.ic_action_person, "个人");
         View i2 = nsTabHost.newTabView(R.layout.tabitem,
                 R.drawable.ic_action_group, "集体");
         View i3 = nsTabHost.newTabView(R.layout.tabitem,
                 R.drawable.ic_action_settings, "设置");
         NsFragmentItem item1 = new NsFragmentItem();
         item1.view = i1;
         item1.tag = TAG_PERSON;
         item1.fragment = PersonFragment.class;
         item1.downStyle = R.drawable.tab_spec_down;
         item1.upStyle = R.drawable.tab_spec_nomal;
         NsFragmentItem item2 = new NsFragmentItem();
         item2.view = i2;
         item2.tag = TAG_GROUP;
         item2.fragment = GroupFragment.class;
         item2.downStyle = R.drawable.tab_spec_down;
         item2.upStyle = R.drawable.tab_spec_nomal;
         NsFragmentItem item3 = new NsFragmentItem();
         item3.view = i3;
         item3.tag = TAG_SETTING;
         item3.fragment = SettingFragment.class;
         item3.downStyle = R.drawable.tab_spec_down;
         item3.upStyle = R.drawable.tab_spec_nomal;
         nsTabHost.AddTab(item1);
         nsTabHost.AddTab(item2);
         nsTabHost.AddTab(item3);
     }
 }